sysnunpm
sysnu is a confirmed malicious npm package (MAL-2026-5617) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.0, 1.0.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in sysnu (npm)
What this malware does
On require() / CLI invocation, sysnu performs two install-time-equivalent actions on Windows hosts. First, if python is not on PATH, index.js (lines 42-46) runs curl -s -L -o <tmp>\python-3.12.3-amd64.exe https://www.python.org/ftp/python/3.12.3/python-3.12.3-amd64.exe and then executes the installer with /quiet InstallAllUsers=0 PrependPath=1, deleting the installer afterwards. Code comments explicitly describe this as a 'GHOST INSTALLER' with 'No UI, No Admin Popup' — i.e., the runtime is provisioned and PATH is mutated with no user consent. Second, index.js line 73 unconditionally runs pip install pyperclip keyboard requests pillow mss pyautogui pywin32 uiautomation comtypes --quiet — a Windows surveillance stack covering keylogging (keyboard), screen capture (mss/pillow), input automation (pyautogui), clipboard scraping (pyperclip), and UI automation (uiautomation/comtypes/pywin32). Index.js line 81 then spawns python pointer.py, but pointer.py is NOT present in the tarball, so the package is a stager awaiting an out-of-band payload that will execute with the freshly-installed surveillance primitives available. The package's advertised purpose ('System binary configuration tool') has no relationship to clipboard/keyboard/screen capture. Metadata is placeholder-grade (author 'ABC', no repository/homepage, generic description), consistent with a throwaway dropper account.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for sysnu (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging sysnu across your stack and pipelines.
If you installed it — respond
sysnu is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If sysnu was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks sysnu before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks sysnu-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.